How to remove water temp sensor/

Was changing mine with the new guages I just put in. The old one snapped clean with the block surface. Now I can't get the rest of it out. I just tried a Craftsman screw out thinking it might work, but it just shaves some of the metal off. I don't want to put a hole in the old sensor unless I know 100% that I can get it all out and not damage the threads, right now there's no leak in the cooling system.

Anyone have any ideas?